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arXiv · 1702.03283

S-matrix singularities and CFT correlation functions

Carlos Cardona·Yu-tin Huang
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Abstract

In this note, we explore the correspondence between four-dimensional flat space S-matrix and two-dimensional CFT proposed by Pasterski et al. We demonstrate that the factorization singularities of an n-point cubic diagram reproduces the AdS Witten diagrams if mass conservation is imposed at each vertex. Such configuration arises naturally if we consider the 4-dimensional S-matrix as a compactified massless 5-dimensional theory. This identification allows us to rewrite the massless S-matrix in the CHY formulation, where the factorization singularities are re-interpreted as factorization limits of a Riemann sphere. In this light, the map is recast into a form of 2d/2d correspondence.

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Carlos Cardona, Yu-tin Huang. 2017-02-10. S-matrix singularities and CFT correlation functions. https://doi.org/10.1007/jhep08(2017)133

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